@nebularstreams/lib-phy/dist/lib.phy.min.js

JavaScript 3D Physics

(function (global, factory) {
  typeof exports === 'object' && typeof module !== 'undefined' ? factory(exports, require('three')) :
  typeof define === 'function' && define.amd ? define(['exports', 'three'], factory) :
  (global = typeof globalThis !== 'undefined' ? globalThis : global || self, factory(global.PhyX = {}, global.THREE));
})(this, (function (exports, three) { 'use strict';

  /**
   * Copyright (c) 2014-present, Facebook, Inc.
   *
   * This source code is licensed under the MIT license found in the
   * LICENSE file in the root directory of this source tree.
   */

  var runtime = (function (exports) {

    var Op = Object.prototype;
    var hasOwn = Op.hasOwnProperty;
    var defineProperty = Object.defineProperty || function (obj, key, desc) { obj[key] = desc.value; };
    var undefined$1; // More compressible than void 0.
    var $Symbol = typeof Symbol === "function" ? Symbol : {};
    var iteratorSymbol = $Symbol.iterator || "@@iterator";
    var asyncIteratorSymbol = $Symbol.asyncIterator || "@@asyncIterator";
    var toStringTagSymbol = $Symbol.toStringTag || "@@toStringTag";

    function define(obj, key, value) {
      Object.defineProperty(obj, key, {
        value: value,
        enumerable: true,
        configurable: true,
        writable: true
      });
      return obj[key];
    }
    try {
      // IE 8 has a broken Object.defineProperty that only works on DOM objects.
      define({}, "");
    } catch (err) {
      define = function(obj, key, value) {
        return obj[key] = value;
      };
    }

    function wrap(innerFn, outerFn, self, tryLocsList) {
      // If outerFn provided and outerFn.prototype is a Generator, then outerFn.prototype instanceof Generator.
      var protoGenerator = outerFn && outerFn.prototype instanceof Generator ? outerFn : Generator;
      var generator = Object.create(protoGenerator.prototype);
      var context = new Context(tryLocsList || []);

      // The ._invoke method unifies the implementations of the .next,
      // .throw, and .return methods.
      defineProperty(generator, "_invoke", { value: makeInvokeMethod(innerFn, self, context) });

      return generator;
    }
    exports.wrap = wrap;

    // Try/catch helper to minimize deoptimizations. Returns a completion
    // record like context.tryEntries[i].completion. This interface could
    // have been (and was previously) designed to take a closure to be
    // invoked without arguments, but in all the cases we care about we
    // already have an existing method we want to call, so there's no need
    // to create a new function object. We can even get away with assuming
    // the method takes exactly one argument, since that happens to be true
    // in every case, so we don't have to touch the arguments object. The
    // only additional allocation required is the completion record, which
    // has a stable shape and so hopefully should be cheap to allocate.
    function tryCatch(fn, obj, arg) {
      try {
        return { type: "normal", arg: fn.call(obj, arg) };
      } catch (err) {
        return { type: "throw", arg: err };
      }
    }

    var GenStateSuspendedStart = "suspendedStart";
    var GenStateSuspendedYield = "suspendedYield";
    var GenStateExecuting = "executing";
    var GenStateCompleted = "completed";

    // Returning this object from the innerFn has the same effect as
    // breaking out of the dispatch switch statement.
    var ContinueSentinel = {};

    // Dummy constructor functions that we use as the .constructor and
    // .constructor.prototype properties for functions that return Generator
    // objects. For full spec compliance, you may wish to configure your
    // minifier not to mangle the names of these two functions.
    function Generator() {}
    function GeneratorFunction() {}
    function GeneratorFunctionPrototype() {}

    // This is a polyfill for %IteratorPrototype% for environments that
    // don't natively support it.
    var IteratorPrototype = {};
    define(IteratorPrototype, iteratorSymbol, function () {
      return this;
    });

    var getProto = Object.getPrototypeOf;
    var NativeIteratorPrototype = getProto && getProto(getProto(values([])));
    if (NativeIteratorPrototype &&
        NativeIteratorPrototype !== Op &&
        hasOwn.call(NativeIteratorPrototype, iteratorSymbol)) {
      // This environment has a native %IteratorPrototype%; use it instead
      // of the polyfill.
      IteratorPrototype = NativeIteratorPrototype;
    }

    var Gp = GeneratorFunctionPrototype.prototype =
      Generator.prototype = Object.create(IteratorPrototype);
    GeneratorFunction.prototype = GeneratorFunctionPrototype;
    defineProperty(Gp, "constructor", { value: GeneratorFunctionPrototype, configurable: true });
    defineProperty(
      GeneratorFunctionPrototype,
      "constructor",
      { value: GeneratorFunction, configurable: true }
    );
    GeneratorFunction.displayName = define(
      GeneratorFunctionPrototype,
      toStringTagSymbol,
      "GeneratorFunction"
    );

    // Helper for defining the .next, .throw, and .return methods of the
    // Iterator interface in terms of a single ._invoke method.
    function defineIteratorMethods(prototype) {
      ["next", "throw", "return"].forEach(function(method) {
        define(prototype, method, function(arg) {
          return this._invoke(method, arg);
        });
      });
    }

    exports.isGeneratorFunction = function(genFun) {
      var ctor = typeof genFun === "function" && genFun.constructor;
      return ctor
        ? ctor === GeneratorFunction ||
          // For the native GeneratorFunction constructor, the best we can
          // do is to check its .name property.
          (ctor.displayName || ctor.name) === "GeneratorFunction"
        : false;
    };

    exports.mark = function(genFun) {
      if (Object.setPrototypeOf) {
        Object.setPrototypeOf(genFun, GeneratorFunctionPrototype);
      } else {
        genFun.__proto__ = GeneratorFunctionPrototype;
        define(genFun, toStringTagSymbol, "GeneratorFunction");
      }
      genFun.prototype = Object.create(Gp);
      return genFun;
    };

    // Within the body of any async function, `await x` is transformed to
    // `yield regeneratorRuntime.awrap(x)`, so that the runtime can test
    // `hasOwn.call(value, "__await")` to determine if the yielded value is
    // meant to be awaited.
    exports.awrap = function(arg) {
      return { __await: arg };
    };

    function AsyncIterator(generator, PromiseImpl) {
      function invoke(method, arg, resolve, reject) {
        var record = tryCatch(generator[method], generator, arg);
        if (record.type === "throw") {
          reject(record.arg);
        } else {
          var result = record.arg;
          var value = result.value;
          if (value &&
              typeof value === "object" &&
              hasOwn.call(value, "__await")) {
            return PromiseImpl.resolve(value.__await).then(function(value) {
              invoke("next", value, resolve, reject);
            }, function(err) {
              invoke("throw", err, resolve, reject);
            });
          }

          return PromiseImpl.resolve(value).then(function(unwrapped) {
            // When a yielded Promise is resolved, its final value becomes
            // the .value of the Promise<{value,done}> result for the
            // current iteration.
            result.value = unwrapped;
            resolve(result);
          }, function(error) {
            // If a rejected Promise was yielded, throw the rejection back
            // into the async generator function so it can be handled there.
            return invoke("throw", error, resolve, reject);
          });
        }
      }

      var previousPromise;

      function enqueue(method, arg) {
        function callInvokeWithMethodAndArg() {
          return new PromiseImpl(function(resolve, reject) {
            invoke(method, arg, resolve, reject);
          });
        }

        return previousPromise =
          // If enqueue has been called before, then we want to wait until
          // all previous Promises have been resolved before calling invoke,
          // so that results are always delivered in the correct order. If
          // enqueue has not been called before, then it is important to
          // call invoke immediately, without waiting on a callback to fire,
          // so that the async generator function has the opportunity to do
          // any necessary setup in a predictable way. This predictability
          // is why the Promise constructor synchronously invokes its
          // executor callback, and why async functions synchronously
          // execute code before the first await. Since we implement simple
          // async functions in terms of async generators, it is especially
          // important to get this right, even though it requires care.
          previousPromise ? previousPromise.then(
            callInvokeWithMethodAndArg,
            // Avoid propagating failures to Promises returned by later
            // invocations of the iterator.
            callInvokeWithMethodAndArg
          ) : callInvokeWithMethodAndArg();
      }

      // Define the unified helper method that is used to implement .next,
      // .throw, and .return (see defineIteratorMethods).
      defineProperty(this, "_invoke", { value: enqueue });
    }

    defineIteratorMethods(AsyncIterator.prototype);
    define(AsyncIterator.prototype, asyncIteratorSymbol, function () {
      return this;
    });
    exports.AsyncIterator = AsyncIterator;

    // Note that simple async functions are implemented on top of
    // AsyncIterator objects; they just return a Promise for the value of
    // the final result produced by the iterator.
    exports.async = function(innerFn, outerFn, self, tryLocsList, PromiseImpl) {
      if (PromiseImpl === void 0) PromiseImpl = Promise;

      var iter = new AsyncIterator(
        wrap(innerFn, outerFn, self, tryLocsList),
        PromiseImpl
      );

      return exports.isGeneratorFunction(outerFn)
        ? iter // If outerFn is a generator, return the full iterator.
        : iter.next().then(function(result) {
            return result.done ? result.value : iter.next();
          });
    };

    function makeInvokeMethod(innerFn, self, context) {
      var state = GenStateSuspendedStart;

      return function invoke(method, arg) {
        if (state === GenStateExecuting) {
          throw new Error("Generator is already running");
        }

        if (state === GenStateCompleted) {
          if (method === "throw") {
            throw arg;
          }

          // Be forgiving, per GeneratorResume behavior specified since ES2015:
          // ES2015 spec, step 3: https://262.ecma-international.org/6.0/#sec-generatorresume
          // Latest spec, step 2: https://tc39.es/ecma262/#sec-generatorresume
          return doneResult();
        }

        context.method = method;
        context.arg = arg;

        while (true) {
          var delegate = context.delegate;
          if (delegate) {
            var delegateResult = maybeInvokeDelegate(delegate, context);
            if (delegateResult) {
              if (delegateResult === ContinueSentinel) continue;
              return delegateResult;
            }
          }

          if (context.method === "next") {
            // Setting context._sent for legacy support of Babel's
            // function.sent implementation.
            context.sent = context._sent = context.arg;

          } else if (context.method === "throw") {
            if (state === GenStateSuspendedStart) {
              state = GenStateCompleted;
              throw context.arg;
            }

            context.dispatchException(context.arg);

          } else if (context.method === "return") {
            context.abrupt("return", context.arg);
          }

          state = GenStateExecuting;

          var record = tryCatch(innerFn, self, context);
          if (record.type === "normal") {
            // If an exception is thrown from innerFn, we leave state ===
            // GenStateExecuting and loop back for another invocation.
            state = context.done
              ? GenStateCompleted
              : GenStateSuspendedYield;

            if (record.arg === ContinueSentinel) {
              continue;
            }

            return {
              value: record.arg,
              done: context.done
            };

          } else if (record.type === "throw") {
            state = GenStateCompleted;
            // Dispatch the exception by looping back around to the
            // context.dispatchException(context.arg) call above.
            context.method = "throw";
            context.arg = record.arg;
          }
        }
      };
    }

    // Call delegate.iterator[context.method](context.arg) and handle the
    // result, either by returning a { value, done } result from the
    // delegate iterator, or by modifying context.method and context.arg,
    // setting context.delegate to null, and returning the ContinueSentinel.
    function maybeInvokeDelegate(delegate, context) {
      var methodName = context.method;
      var method = delegate.iterator[methodName];
      if (method === undefined$1) {
        // A .throw or .return when the delegate iterator has no .throw
        // method, or a missing .next method, always terminate the
        // yield* loop.
        context.delegate = null;

        // Note: ["return"] must be used for ES3 parsing compatibility.
        if (methodName === "throw" && delegate.iterator["return"]) {
          // If the delegate iterator has a return method, give it a
          // chance to clean up.
          context.method = "return";
          context.arg = undefined$1;
          maybeInvokeDelegate(delegate, context);

          if (context.method === "throw") {
            // If maybeInvokeDelegate(context) changed context.method from
            // "return" to "throw", let that override the TypeError below.
            return ContinueSentinel;
          }
        }
        if (methodName !== "return") {
          context.method = "throw";
          context.arg = new TypeError(
            "The iterator does not provide a '" + methodName + "' method");
        }

        return ContinueSentinel;
      }

      var record = tryCatch(method, delegate.iterator, context.arg);

      if (record.type === "throw") {
        context.method = "throw";
        context.arg = record.arg;
        context.delegate = null;
        return ContinueSentinel;
      }

      var info = record.arg;

      if (! info) {
        context.method = "throw";
        context.arg = new TypeError("iterator result is not an object");
        context.delegate = null;
        return ContinueSentinel;
      }

      if (info.done) {
        // Assign the result of the finished delegate to the temporary
        // variable specified by delegate.resultName (see delegateYield).
        context[delegate.resultName] = info.value;

        // Resume execution at the desired location (see delegateYield).
        context.next = delegate.nextLoc;

        // If context.method was "throw" but the delegate handled the
        // exception, let the outer generator proceed normally. If
        // context.method was "next", forget context.arg since it has been
        // "consumed" by the delegate iterator. If context.method was
        // "return", allow the original .return call to continue in the
        // outer generator.
        if (context.method !== "return") {
          context.method = "next";
          context.arg = undefined$1;
        }

      } else {
        // Re-yield the result returned by the delegate method.
        return info;
      }

      // The delegate iterator is finished, so forget it and continue with
      // the outer generator.
      context.delegate = null;
      return ContinueSentinel;
    }

    // Define Generator.prototype.{next,throw,return} in terms of the
    // unified ._invoke helper method.
    defineIteratorMethods(Gp);

    define(Gp, toStringTagSymbol, "Generator");

    // A Generator should always return itself as the iterator object when the
    // @@iterator function is called on it. Some browsers' implementations of the
    // iterator prototype chain incorrectly implement this, causing the Generator
    // object to not be returned from this call. This ensures that doesn't happen.
    // See https://github.com/facebook/regenerator/issues/274 for more details.
    define(Gp, iteratorSymbol, function() {
      return this;
    });

    define(Gp, "toString", function() {
      return "[object Generator]";
    });

    function pushTryEntry(locs) {
      var entry = { tryLoc: locs[0] };

      if (1 in locs) {
        entry.catchLoc = locs[1];
      }

      if (2 in locs) {
        entry.finallyLoc = locs[2];
        entry.afterLoc = locs[3];
      }

      this.tryEntries.push(entry);
    }

    function resetTryEntry(entry) {
      var record = entry.completion || {};
      record.type = "normal";
      delete record.arg;
      entry.completion = record;
    }

    function Context(tryLocsList) {
      // The root entry object (effectively a try statement without a catch
      // or a finally block) gives us a place to store values thrown from
      // locations where there is no enclosing try statement.
      this.tryEntries = [{ tryLoc: "root" }];
      tryLocsList.forEach(pushTryEntry, this);
      this.reset(true);
    }

    exports.keys = function(val) {
      var object = Object(val);
      var keys = [];
      for (var key in object) {
        keys.push(key);
      }
      keys.reverse();

      // Rather than returning an object with a next method, we keep
      // things simple and return the next function itself.
      return function next() {
        while (keys.length) {
          var key = keys.pop();
          if (key in object) {
            next.value = key;
            next.done = false;
            return next;
          }
        }

        // To avoid creating an additional object, we just hang the .value
        // and .done properties off the next function object itself. This
        // also ensures that the minifier will not anonymize the function.
        next.done = true;
        return next;
      };
    };

    function values(iterable) {
      if (iterable != null) {
        var iteratorMethod = iterable[iteratorSymbol];
        if (iteratorMethod) {
          return iteratorMethod.call(iterable);
        }

        if (typeof iterable.next === "function") {
          return iterable;
        }

        if (!isNaN(iterable.length)) {
          var i = -1, next = function next() {
            while (++i < iterable.length) {
              if (hasOwn.call(iterable, i)) {
                next.value = iterable[i];
                next.done = false;
                return next;
              }
            }

            next.value = undefined$1;
            next.done = true;

            return next;
          };

          return next.next = next;
        }
      }

      throw new TypeError(typeof iterable + " is not iterable");
    }
    exports.values = values;

    function doneResult() {
      return { value: undefined$1, done: true };
    }

    Context.prototype = {
      constructor: Context,

      reset: function(skipTempReset) {
        this.prev = 0;
        this.next = 0;
        // Resetting context._sent for legacy support of Babel's
        // function.sent implementation.
        this.sent = this._sent = undefined$1;
        this.done = false;
        this.delegate = null;

        this.method = "next";
        this.arg = undefined$1;

        this.tryEntries.forEach(resetTryEntry);

        if (!skipTempReset) {
          for (var name in this) {
            // Not sure about the optimal order of these conditions:
            if (name.charAt(0) === "t" &&
                hasOwn.call(this, name) &&
                !isNaN(+name.slice(1))) {
              this[name] = undefined$1;
            }
          }
        }
      },

      stop: function() {
        this.done = true;

        var rootEntry = this.tryEntries[0];
        var rootRecord = rootEntry.completion;
        if (rootRecord.type === "throw") {
          throw rootRecord.arg;
        }

        return this.rval;
      },

      dispatchException: function(exception) {
        if (this.done) {
          throw exception;
        }

        var context = this;
        function handle(loc, caught) {
          record.type = "throw";
          record.arg = exception;
          context.next = loc;

          if (caught) {
            // If the dispatched exception was caught by a catch block,
            // then let that catch block handle the exception normally.
            context.method = "next";
            context.arg = undefined$1;
          }

          return !! caught;
        }

        for (var i = this.tryEntries.length - 1; i >= 0; --i) {
          var entry = this.tryEntries[i];
          var record = entry.completion;

          if (entry.tryLoc === "root") {
            // Exception thrown outside of any try block that could handle
            // it, so set the completion value of the entire function to
            // throw the exception.
            return handle("end");
          }

          if (entry.tryLoc <= this.prev) {
            var hasCatch = hasOwn.call(entry, "catchLoc");
            var hasFinally = hasOwn.call(entry, "finallyLoc");

            if (hasCatch && hasFinally) {
              if (this.prev < entry.catchLoc) {
                return handle(entry.catchLoc, true);
              } else if (this.prev < entry.finallyLoc) {
                return handle(entry.finallyLoc);
              }

            } else if (hasCatch) {
              if (this.prev < entry.catchLoc) {
                return handle(entry.catchLoc, true);
              }

            } else if (hasFinally) {
              if (this.prev < entry.finallyLoc) {
                return handle(entry.finallyLoc);
              }

            } else {
              throw new Error("try statement without catch or finally");
            }
          }
        }
      },

      abrupt: function(type, arg) {
        for (var i = this.tryEntries.length - 1; i >= 0; --i) {
          var entry = this.tryEntries[i];
          if (entry.tryLoc <= this.prev &&
              hasOwn.call(entry, "finallyLoc") &&
              this.prev < entry.finallyLoc) {
            var finallyEntry = entry;
            break;
          }
        }

        if (finallyEntry &&
            (type === "break" ||
             type === "continue") &&
            finallyEntry.tryLoc <= arg &&
            arg <= finallyEntry.finallyLoc) {
          // Ignore the finally entry if control is not jumping to a
          // location outside the try/catch block.
          finallyEntry = null;
        }

        var record = finallyEntry ? finallyEntry.completion : {};
        record.type = type;
        record.arg = arg;

        if (finallyEntry) {
          this.method = "next";
          this.next = finallyEntry.finallyLoc;
          return ContinueSentinel;
        }

        return this.complete(record);
      },

      complete: function(record, afterLoc) {
        if (record.type === "throw") {
          throw record.arg;
        }

        if (record.type === "break" ||
            record.type === "continue") {
          this.next = record.arg;
        } else if (record.type === "return") {
          this.rval = this.arg = record.arg;
          this.method = "return";
          this.next = "end";
        } else if (record.type === "normal" && afterLoc) {
          this.next = afterLoc;
        }

        return ContinueSentinel;
      },

      finish: function(finallyLoc) {
        for (var i = this.tryEntries.length - 1; i >= 0; --i) {
          var entry = this.tryEntries[i];
          if (entry.finallyLoc === finallyLoc) {
            this.complete(entry.completion, entry.afterLoc);
            resetTryEntry(entry);
            return ContinueSentinel;
          }
        }
      },

      "catch": function(tryLoc) {
        for (var i = this.tryEntries.length - 1; i >= 0; --i) {
          var entry = this.tryEntries[i];
          if (entry.tryLoc === tryLoc) {
            var record = entry.completion;
            if (record.type === "throw") {
              var thrown = record.arg;
              resetTryEntry(entry);
            }
            return thrown;
          }
        }

        // The context.catch method must only be called with a location
        // argument that corresponds to a known catch block.
        throw new Error("illegal catch attempt");
      },

      delegateYield: function(iterable, resultName, nextLoc) {
        this.delegate = {
          iterator: values(iterable),
          resultName: resultName,
          nextLoc: nextLoc
        };

        if (this.method === "next") {
          // Deliberately forget the last sent value so that we don't
          // accidentally pass it on to the delegate.
          this.arg = undefined$1;
        }

        return ContinueSentinel;
      }
    };

    // Regardless of whether this script is executing as a CommonJS module
    // or not, return the runtime object so that we can declare the variable
    // regeneratorRuntime in the outer scope, which allows this module to be
    // injected easily by `bin/regenerator --include-runtime script.js`.
    return exports;

  }(
    // If this script is executing as a CommonJS module, use module.exports
    // as the regeneratorRuntime namespace. Otherwise create a new empty
    // object. Either way, the resulting object will be used to initialize
    // the regeneratorRuntime variable at the top of this file.
    typeof module === "object" ? module.exports : {}
  ));

  try {
    regeneratorRuntime = runtime;
  } catch (accidentalStrictMode) {
    // This module should not be running in strict mode, so the above
    // assignment should always work unless something is misconfigured. Just
    // in case runtime.js accidentally runs in strict mode, in modern engines
    // we can explicitly access globalThis. In older engines we can escape
    // strict mode using a global Function call. This could conceivably fail
    // if a Content Security Policy forbids using Function, but in that case
    // the proper solution is to fix the accidental strict mode problem. If
    // you've misconfigured your bundler to force strict mode and applied a
    // CSP to forbid Function, and you're not willing to fix either of those
    // problems, please detail your unique predicament in a GitHub issue.
    if (typeof globalThis === "object") {
      globalThis.regeneratorRuntime = runtime;
    } else {
      Function("r", "regeneratorRuntime = r")(runtime);
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function DRACOWorker() {

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	let decoderPending;

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						// Module is Promise-like. Wrap before resolving to avoid loop.
						resolve( { draco: draco } );

					};

					DracoDecoderModule( decoderConfig ); // eslint-disable-line no-undef

				} );
				break;

			case 'decode':
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				decoderPending.then( ( module ) => {

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			decodingStatus = decoder.DecodeArrayToPointCloud( array, array.byteLength, dracoGeometry );

		} else {

			throw new Error( 'THREE.DRACOLoader: Unexpected geometry type.' );

		}

		if ( ! decodingStatus.ok() || dracoGeometry.ptr === 0 ) {

			throw new Error( 'THREE.DRACOLoader: Decoding failed: ' + decodingStatus.error_msg() );

		}

		const geometry = { index: null, attributes: [] };

		// Gather all vertex attributes.
		for ( const attributeName in attributeIDs ) {

			const attributeType = self[ attributeTypes[ attributeName ] ];

			let attribute;
			let attributeID;

			// A Draco file may be created with default vertex attributes, whose attribute IDs
			// are mapped 1:1 from their semantic name (POSITION, NORMAL, ...). Alternatively,
			// a Draco file may contain a custom set of attributes, identified by known unique
			// IDs. glTF files always do the latter, and .drc files typically do the former.

			if ( taskConfig.useUniqueIDs ) {

				attributeID = attributeIDs[ attributeName ];
				attribute = decoder.GetAttributeByUniqueId( dracoGeometry, attributeID );

			} else {

				attributeID = decoder.GetAttributeId( dracoGeometry, draco[ attributeIDs[ attributeName ] ] );

				if ( attributeID === - 1 ) continue;

				attribute = decoder.GetAttribute( dracoGeometry, attributeID );

			}

			const attributeResult = decodeAttribute( draco, decoder, dracoGeometry, attributeName, attributeType, attribute );

			if ( attributeName === 'color' ) {

				attributeResult.vertexColorSpace = taskConfig.vertexColorSpace;

			}

			geometry.attributes.push( attributeResult );

		}

		// Add index.
		if ( geometryType === draco.TRIANGULAR_MESH ) {

			geometry.index = decodeIndex( draco, decoder, dracoGeometry );

		}

		draco.destroy( dracoGeometry );

		return geometry;

	}

	function decodeIndex( draco, decoder, dracoGeometry ) {

		const numFaces = dracoGeometry.num_faces();
		const numIndices = numFaces * 3;
		const byteLength = numIndices * 4;

		const ptr = draco._malloc( byteLength );
		decoder.GetTrianglesUInt32Array( dracoGeometry, byteLength, ptr );
		const index = new Uint32Array( draco.HEAPF32.buffer, ptr, numIndices ).slice();
		draco._free( ptr );

		return { array: index, itemSize: 1 };

	}

	function decodeAttribute( draco, decoder, dracoGeometry, attributeName, attributeType, attribute ) {

		const numComponents = attribute.num_components();
		const numPoints = dracoGeometry.num_points();
		const numValues = numPoints * numComponents;
		const byteLength = numValues * attributeType.BYTES_PER_ELEMENT;
		const dataType = getDracoDataType( draco, attributeType );

		const ptr = draco._malloc( byteLength );
		decoder.GetAttributeDataArrayForAllPoints( dracoGeometry, attribute, dataType, byteLength, ptr );
		const array = new attributeType( draco.HEAPF32.buffer, ptr, numValues ).slice();
		draco._free( ptr );

		return {
			name: attributeName,
			array: array,
			itemSize: numComponents
		};

	}

	function getDracoDataType( draco, attributeType ) {

		switch ( attributeType ) {

			case Float32Array: return draco.DT_FLOAT32;
			case Int8Array: return draco.DT_INT8;
			case Int16Array: return draco.DT_INT16;
			case Int32Array: return draco.DT_INT32;
			case Uint8Array: return draco.DT_UINT8;
			case Uint16Array: return draco.DT_UINT16;
			case Uint32Array: return draco.DT_UINT32;

		}

	}

}
`;

  class DRACOLoader extends three.Loader {

  	constructor(manager) {

  		super(manager);

  		this.decoderPath = '';
  		this.decoderConfig = {};
  		this.decoderBinary = null;
  		this.decoderPending = null;

  		this.workerLimit = 4;
  		this.workerPool = [];
  		this.workerNextTaskID = 1;
  		this.workerSourceURL = '';

  		this.defaultAttributeIDs = {
  			position: 'POSITION',
  			normal: 'NORMAL',
  			color: 'COLOR',
  			uv: 'TEX_COORD'
  		};
  		this.defaultAttributeTypes = {
  			position: 'Float32Array',
  			normal: 'Float32Array',
  			color: 'Float32Array',
  			uv: 'Float32Array'
  		};

  	}

  	setDecoderPath(path) {

  		this.decoderPath = path;

  		return this;

  	}

  	setDecoderConfig(config) {

  		this.decoderConfig = config;

  		return this;

  	}

  	setWorkerLimit(workerLimit) {

  		this.workerLimit = workerLimit;

  		return this;

  	}

  	load(url, onLoad, onProgress, onError) {

  		const loader = new three.FileLoader(this.manager);

  		loader.setPath(this.path);
  		loader.setResponseType('arraybuffer');
  		loader.setRequestHeader(this.requestHeader);
  		loader.setWithCredentials(this.withCredentials);

  		loader.load(url, (buffer) => {

  			this.parse(buffer, onLoad, onError);

  		}, onProgress, onError);

  	}

  	parse(buffer, onLoad, onError) {

  		this.decodeDracoFile(buffer, onLoad, null, null, three.SRGBColorSpace).catch(onError);

  	}

  	decodeDracoFile(buffer, callback, attributeIDs, attributeTypes, vertexColorSpace = three.LinearSRGBColorSpace) {

  		const taskConfig = {
  			attributeIDs: attributeIDs || this.defaultAttributeIDs,
  			attributeTypes: attributeTypes || this.defaultAttributeTypes,
  			useUniqueIDs: !!attributeIDs,
  			vertexColorSpace: vertexColorSpace,
  		};

  		return this.decodeGeometry(buffer, taskConfig).then(callback);

  	}

  	decodeGeometry(buffer, taskConfig) {

  		const taskKey = JSON.stringify(taskConfig);

  		// Check for an existing task using this buffer. A transferred buffer cannot be transferred
  		// again from this thread.
  		if (_taskCache.has(buffer)) {

  			const cachedTask = _taskCache.get(buffer);

  			if (cachedTask.key === taskKey) {

  				return cachedTask.promise;

  			} else if (buffer.byteLength === 0) {

  				// Technically, it would be possible to wait for the previous task to complete,
  				// transfer the buffer back, and decode again with the second configuration. That
  				// is complex, and I don't know of any reason to decode a Draco buffer twice in
  				// different ways, so this is left unimplemented.
  				throw new Error(
  					'THREE.DRACOLoader: Unable to re-decode a buffer with different ' +
  					'settings. Buffer has already been transferred.'
  				);

  			}

  		}

  		//

  		let worker;
  		const taskID = this.workerNextTaskID++;
  		const taskCost = buffer.byteLength;

  		// Obtain a worker and assign a task, and construct a geometry instance
  		// when the task completes.
  		const geometryPending = this._getWorker(taskID, taskCost)
  			.then((_worker) => {

  				worker = _worker;

  				return new Promise((resolve, reject) => {

  					worker._callbacks[taskID] = {resolve, reject};

  					worker.postMessage({type: 'decode', id: taskID, taskConfig, buffer}, [buffer]);

  					// this.debug();

  				});

  			})
  			.then((message) => this._createGeometry(message.geometry));

  		// Remove task from the task list.
  		// Note: replaced '.finally()' with '.catch().then()' block - iOS 11 support (#19416)
  		geometryPending
  			.catch(() => true)
  			.then(() => {

  				if (worker && taskID) {

  					this._releaseTask(worker, taskID);

  					// this.debug();

  				}

  			});

  		// Cache the task result.
  		_taskCache.set(buffer, {

  			key: taskKey,
  			promise: geometryPending

  		});

  		return geometryPending;

  	}

  	_createGeometry(geometryData) {

  		const geometry = new three.BufferGeometry();

  		if (geometryData.index) {

  			geometry.setIndex(new three.BufferAttribute(geometryData.index.array, 1));

  		}

  		for (let i = 0; i < geometryData.attributes.length; i++) {

  			const result = geometryData.attributes[i];
  			const name = result.name;
  			const array = result.array;
  			const itemSize = result.itemSize;

  			const attribute = new three.BufferAttribute(array, itemSize);

  			if (name === 'color') {

  				this._assignVertexColorSpace(attribute, result.vertexColorSpace);

  				attribute.normalized = (array instanceof Float32Array) === false;

  			}

  			geometry.setAttribute(name, attribute);

  		}

  		return geometry;

  	}

  	_assignVertexColorSpace(attribute, inputColorSpace) {

  		// While .drc files do not specify colorspace, the only 'official' tooling
  		// is PLY and OBJ converters, which use sRGB. We'll assume sRGB when a .drc
  		// file is passed into .load() or .parse(). GLTFLoader uses internal APIs
  		// to decode geometry, and vertex colors are already Linear-sRGB in there.

  		if (inputColorSpace !== three.SRGBColorSpace) return;

  		const _color = new three.Color();

  		for (let i = 0, il = attribute.count; i < il; i++) {

  			_color.fromBufferAttribute(attribute, i).convertSRGBToLinear();
  			attribute.setXYZ(i, _color.r, _color.g, _color.b);

  		}

  	}

  	_loadLibrary(url, responseType) {

  		const loader = new three.FileLoader(this.manager);
  		loader.setPath(this.decoderPath);
  		loader.setResponseType(responseType);
  		loader.setWithCredentials(this.withCredentials);

  		return new Promise((resolve, reject) => {

  			loader.load(url, resolve, undefined, reject);

  		});

  	}

  	preload() {

  		this._initDecoder();

  		return this;

  	}

  	_initDecoder() {

  		if (this.decoderPending) return this.decoderPending;

  		const useJS = typeof WebAssembly !== 'object' || this.decoderConfig.type === 'js';
  		const librariesPending = [];

  		if (useJS) {

  			librariesPending.push(this._loadLibrary('draco_decoder.js', 'text'));

  		} else {

  			librariesPending.push(this._loadLibrary('draco_wasm_wrapper.js', 'text'));
  			librariesPending.push(this._loadLibrary('draco_decoder.wasm', 'arraybuffer'));

  		}

  		this.decoderPending = Promise.all(librariesPending)
  			.then((libraries) => {

  				const jsContent = libraries[0];

  				if (!useJS) {

  					this.decoderConfig.wasmBinary = libraries[1];

  				}

  				const fn = DRACOWorker.toString();

  				const body = [
  					'/* draco decoder */',
  					jsContent,
  					'',
  					'/* worker */',
  					fn.substring(fn.indexOf('{') + 1, fn.lastIndexOf('}'))
  				].join('\n');

  				this.workerSourceURL = URL.createObjectURL(new Blob([body]));

  			});

  		return this.decoderPending;

  	}

  	_getWorker(taskID, taskCost) {

  		return this._initDecoder().then(() => {

  			if (this.workerPool.length < this.workerLimit) {

  				const worker = new Worker(this.workerSourceURL);

  				worker._callbacks = {};
  				worker._taskCosts = {};
  				worker._taskLoad = 0;

  				worker.postMessage({type: 'init', decoderConfig: this.decoderConfig});

  				worker.onmessage = function (e) {

  					const message = e.data;

  					switch (message.type) {

  						case 'decode':
  							worker._callbacks[message.id].resolve(message);
  							break;

  						case 'error':
  							worker._callbacks[message.id].reject(message);
  							break;

  						default:
  							console.error('THREE.DRACOLoader: Unexpected message, "' + message.type + '"');

  					}

  				};

  				this.workerPool.push(worker);

  			} else {

  				this.workerPool.sort(function (a, b) {

  					return a._taskLoad > b._taskLoad ? -1 : 1;

  				});

  			}

  			const worker = this.workerPool[this.workerPool.length - 1];
  			worker._taskCosts[taskID] = taskCost;
  			worker._taskLoad += taskCost;
  			return worker;

  		});

  	}

  	_releaseTask(worker, taskID) {

  		worker._taskLoad -= worker._taskCosts[taskID];
  		delete worker._callbacks[taskID];
  		delete worker._taskCosts[taskID];

  	}

  	debug() {

  		console.log('Task load: ', this.workerPool.map((worker) => worker._taskLoad));

  	}

  	dispose() {

  		for (let i = 0; i < this.workerPool.length; ++i) {

  			this.workerPool[i].terminate();

  		}

  		this.workerPool.length = 0;

  		if (this.workerSourceURL !== '') {

  			URL.revokeObjectURL(this.workerSourceURL);

  		}

  		return this;

  	}

  }

  function computeMikkTSpaceTangents( geometry, MikkTSpace, negateSign = true ) {

  	if ( ! MikkTSpace || ! MikkTSpace.isReady ) {

  		throw new Error( 'BufferGeometryUtils: Initialized MikkTSpace library required.' );

  	}

  	if ( ! geometry.hasAttribute( 'position' ) || ! geometry.hasAttribute( 'normal' ) || ! geometry.hasAttribute( 'uv' ) ) {

  		throw new Error( 'BufferGeometryUtils: Tangents require "position", "normal", and "uv" attributes.' );

  	}

  	function getAttributeArray( attribute ) {

  		if ( attribute.normalized || attribute.isInterleavedBufferAttribute ) {

  			const dstArray = new Float32Array( attribute.count * attribute.itemSize );

  			for ( let i = 0, j = 0; i < attribute.count; i ++ ) {

  				dstArray[ j ++ ] = attribute.getX( i );
  				dstArray[ j ++ ] = attribute.getY( i );

  				if ( attribute.itemSize > 2 ) {

  					dstArray[ j ++ ] = attribute.getZ( i );

  				}

  			}

  			return dstArray;

  		}

  		if ( attribute.array instanceof Float32Array ) {

  			return attribute.array;

  		}

  		return new Float32Array( attribute.array );

  	}

  	// MikkTSpace algorithm requires non-indexed input.

  	const _geometry = geometry.index ? geometry.toNonIndexed() : geometry;

  	// Compute vertex tangents.

  	const tangents = MikkTSpace.generateTangents(

  		getAttributeArray( _geometry.attributes.position ),
  		getAttributeArray( _geometry.attributes.normal ),
  		getAttributeArray( _geometry.attributes.uv )

  	);

  	// Texture coordinate convention of glTF differs from the apparent
  	// default of the MikkTSpace library; .w component must be flipped.

  	if ( negateSign ) {

  		for ( let i = 3; i < tangents.length; i += 4 ) {

  			tangents[ i ] *= -1;

  		}

  	}

  	//

  	_geometry.setAttribute( 'tangent', new three.BufferAttribute( tangents, 4 ) );

  	if ( geometry !== _geometry ) {

  		geometry.copy( _geometry );

  	}

  	return geometry;

  }

  /**
   * @param  {Array<BufferGeometry>} geometries
   * @param  {Boolean} useGroups
   * @return {BufferGeometry}
   */
  function mergeGeometries( geometries, useGroups = false ) {

  	const isIndexed = geometries[ 0 ].index !== null;

  	const attributesUsed = new Set( Object.keys( geometries[ 0 ].attributes ) );
  	const morphAttributesUsed = new Set( Object.keys( geometries[ 0 ].morphAttributes ) );

  	const attributes = {};
  	const morphAttributes = {};

  	const morphTargetsRelative = geometries[ 0 ].morphTargetsRelative;

  	const mergedGeometry = new three.BufferGeometry();

  	let offset = 0;

  	for ( let i = 0; i < geometries.length; ++ i ) {

  		const geometry = geometries[ i ];
  		let attributesCount = 0;

  		// ensure that all geometries are indexed, or none

  		if ( isIndexed !== ( geometry.index !== null ) ) {

  			console.error( 'THREE.BufferGeometryUtils: .mergeGeometries() failed with geometry at index ' + i + '. All geometries must have compatible attributes; make sure index attribute exists among all geometries, or in none of them.' );
  			return null;

  		}

  		// gather attributes, exit early if they're different

  		for ( const name in geometry.attributes ) {

  			if ( ! attributesUsed.has( name ) ) {

  				console.error( 'THREE.BufferGeometryUtils: .mergeGeometries() failed with geometry at index ' + i + '. All geometries must have compatible attributes; make sure "' + name + '" attribute exists among all geometries, or in none of them.' );
  				return null;

  			}

  			if ( attributes[ name ] === undefined ) attributes[ name ] = [];

  			attributes[ name ].push( geometry.attributes[ name ] );

  			attributesCount ++;

  		}

  		// ensure geometries have the same number of attributes

  		if ( attributesCount !== attributesUsed.size ) {

  			console.error( 'THREE.BufferGeometryUtils: .mergeGeometries() failed with geometry at index ' + i + '. Make sure all geometries have the same number of attributes.' );
  			return null;

  		}

  		// gather morph attributes, exit early if they're different

  		if ( morphTargetsRelative !== geometry.morphTargetsRelative ) {

  			console.error( 'THREE.BufferGeometryUtils: .mergeGeometries() failed with geometry at index ' + i + '. .morphTargetsRelative must be consistent throughout all geometries.' );
  			return null;

  		}

  		for ( const name in geometry.morphAttributes ) {

  			if ( ! morphAttributesUsed.has( name ) ) {

  				console.error( 'THREE.BufferGeometryUtils: .mergeGeometries() failed with geometry at index ' + i + '.  .morphAttributes must be consistent throughout all geometries.' );
  				return null;

  			}

  			if ( morphAttributes[ name ] === undefined ) morphAttributes[ name ] = [];

  			morphAttributes[ name ].push( geometry.morphAttributes[ name ] );

  		}

  		if ( useGroups ) {

  			let count;

  			if ( isIndexed ) {

  				count = geometry.index.count;

  			} else if ( geometry.attributes.position !== undefined ) {

  				count = geometry.attributes.position.count;

  			} else {

  				console.error( 'THREE.BufferGeometryUtils: .mergeGeometries() failed with geometry at index ' + i + '. The geometry must have either an index or a position attribute' );
  				return null;

  			}

  			mergedGeometry.addGroup( offset, count, i );

  			offset += count;

  		}

  	}

  	// merge indices

  	if ( isIndexed ) {

  		let indexOffset = 0;
  		const mergedIndex = [];

  		for ( let i = 0; i < geometries.length; ++ i ) {

  			const index = geometries[ i ].index;

  			for ( let j = 0; j < index.count; ++ j ) {

  				mergedIndex.push( index.getX( j ) + indexOffset );

  			}

  			indexOffset += geometries[ i ].attributes.position.count;

  		}

  		mergedGeometry.setIndex( mergedIndex );

  	}

  	// merge attributes

  	for ( const name in attributes ) {

  		const mergedAttribute = mergeAttributes( attributes[ name ] );

  		if ( ! mergedAttribute ) {

  			console.error( 'THREE.BufferGeometryUtils: .mergeGeometries() failed while trying to merge the ' + name + ' attribute.' );
  			return null;

  		}

  		mergedGeometry.setAttribute( name, mergedAttribute );

  	}

  	// merge morph attributes

  	for ( const name in morphAttributes ) {

  		const numMorphTargets = morphAttributes[ name ][ 0 ].length;

  		if ( numMorphTargets === 0 ) break;

  		mergedGeometry.morphAttributes = mergedGeometry.morphAttributes || {};
  		mergedGeometry.morphAttributes[ name ] = [];

  		for ( let i = 0; i < numMorphTargets; ++ i ) {

  			const morphAttributesToMerge = [];

  			for ( let j = 0; j < morphAttributes[ name ].length; ++ j ) {

  				morphAttributesToMerge.push( morphAttributes[ name ][ j ][ i ] );

  			}

  			const mergedMorphAttribute = mergeAttributes( morphAttributesToMerge );

  			if ( ! mergedMorphAttribute ) {

  				console.error( 'THREE.BufferGeometryUtils: .mergeGeometries() failed while trying to merge the ' + name + ' morphAttribute.' );
  				return null;

  			}

  			mergedGeometry.morphAttributes[ name ].push( mergedMorphAttribute );

  		}

  	}

  	return mergedGeometry;

  }

  /**
   * @param {Array<BufferAttribute>} attributes
   * @return {BufferAttribute}
   */
  function mergeAttributes( attributes ) {

  	let TypedArray;
  	let itemSize;
  	let normalized;
  	let gpuType = -1;
  	let arrayLength = 0;

  	for ( let i = 0; i < attributes.length; ++ i ) {

  		const attribute = attributes[ i ];

  		if ( TypedArray === undefined ) TypedArray = attribute.array.constructor;
  		if ( TypedArray !== attribute.array.constructor ) {

  			console.error( 'THREE.BufferGeometryUtils: .mergeAttributes() failed. BufferAttribute.array must be of consistent array types across matching attributes.' );
  			return null;

  		}

  		if ( itemSize === undefined ) itemSize = attribute.itemSize;
  		if ( itemSize !== attribute.itemSize ) {

  			console.error( 'THREE.BufferGeometryUtils: .mergeAttributes() failed. BufferAttribute.itemSize must be consistent across matching attributes.' );
  			return null;

  		}

  		if ( normalized === undefined ) normalized = attribute.normalized;
  		if ( normalized !== attribute.normalized ) {

  			console.error( 'THREE.BufferGeometryUtils: .mergeAttributes() failed. BufferAttribute.normalized must be consistent across matching attributes.' );
  			return null;

  		}

  		if ( gpuType === -1 ) gpuType = attribute.gpuType;
  		if ( gpuType !== attribute.gpuType ) {

  			console.error( 'THREE.BufferGeometryUtils: .mergeAttributes() failed. BufferAttribute.gpuType must be consistent across matching attributes.' );
  			return null;

  		}

  		arrayLength += attribute.count * itemSize;

  	}

  	const array = new TypedArray( arrayLength );
  	const result = new three.BufferAttribute( array, itemSize, normalized );
  	let offset = 0;

  	for ( let i = 0; i < attributes.length; ++ i ) {

  		const attribute = attributes[ i ];
  		if ( attribute.isInterleavedBufferAttribute ) {

  			const tupleOffset = offset / itemSize;
  			for ( let j = 0, l = attribute.count; j < l; j ++ ) {

  				for ( let c = 0; c < itemSize; c ++ ) {

  					const value = attribute.getComponent( j, c );
  					result.setComponent( j + tupleOffset, c, value );

  				}

  			}

  		} else {

  			array.set( attribute.array, offset );

  		}

  		offset += attr